Dominique's, the Pennsylvania Avenue French restaurant known for its exotic menu, wants to open a branch in Prince George's County, but the county's planning commission isn't satisfied with the financial backing of the developers.

The restaurant would be part of a $15 million renovation of the 47-year-old White Mansion, which sits on a 586-acre estate off Enterprise Road in a semi-rural area between Glenarden and Bowie.

The park and planning commission purchased the property a few years ago to preserve it as a historic site. The commission, which must approve the leasing arrangement, insisted yesterday that the developers find a major financial backer or provide other guarantees for the project.

Commission Chairman Charles Dukes Jr. said that in the event the project fails, he wants to insure that the county will be able to collect the $2 million annual rent over the 20 years of the lease.

Developers T. Conrad Monts and Alvin Turner balked at the commission's terms. "What is being exacted from these (developers) is being exacted from no others in the United States, I believe," said their attorney, Russell Shipley.

But Dukes insisted, "I want you to show me a somebody who can guarantee some money."

After an acerbic meeting with the developers yesterday, the commission postponed a decision for a week to give the developers a chance to prove they have the financial backing that the commission would find acceptable.

"We will attempt to comply with that request," Monts said after the meeting.

Two years ago, the commission began seeking a private concern to lease the premises. Both Dukes and commission vice chairman Edgar Brown said they were attracted to the Monts-Turner proposal in large part because a successful restaurant such as Dominque's would be involved. Monts said yesterday that Dominique D'Ermo, the restaurant owner, is still interested but is awaiting the outcome of the lease negotiations. D'Ermo could not be reached for comment.

Representatives of Monts and Turner suggested that they think part of the reason the planning commission is being so conservative is that Monts is black. They said the commission has not asked other businesses to provide the same guarantees, specifically pointing to Abe Pollin, whose Capital Centre arena is on park and planning property.

"I don't think there's any racial issue at all," said Brown, one of two black members of the commission. "It's a question of what is beneficial for the county."

"I think you have to take each situation as it comes," Brown said. "This is an innovative project, the first of its kind in the county."

Dukes said he envisions the convention center operating like Airlie House in Virginia, which is used by corporate executives for planning sessions, seminars and retreats.

Dukes said the county wants Dominique's to preserve the original character of the mansion. The house, formerly owned by Newton White, the first commander of the U.S.S. Enterprise, is now used for wedding receptions and political functions The property includes an 18-hole golf course. CAPTION: Picture, A new Dominique's French restaurant is part of the planned $15 million renovation of the White Mansion in Prince George County. By James A. Parcell--The Washington Post